MATERIAL and METHODS: We retrospectively reviewed 199 patients who were treated with Gamma-Knife RS for intracranial
AVMs between 13 October 2005 and 31 October 2010. There were 89 male, 110 female patients with a median age of 32 years
(range, 3-74 years). Obliteration was assessed with MRI angiography and DSA imaging.

RESULTS: Complete obliteration rate after RS was 71 % (141 out of 199), including second RS treatments. In terms of obliteration
rates, there was no significant difference between patients younger and older than 21 years old (p=0.669). After RS, 3 patients died
due to intracranial hemorrhage and 1 died of heart disease. Death from AVM was determined as 1.5 %. Intracranial hemorrhage was
observed in 7 (3.5 %) patients post-RS.

CONCLUSION: Obliteration was found to be associated with Spetzler-Martin Grade, Pollock-Flickinger Grade, AVM volume, RS
dose, bleeding history before RS and no previous embolization before RS. Gamma knife RS is an effective treatment method for the
treatment of AVMs both for pediatric and adult patients. It provides high obliteration and low mortality rates.